The present invention relates generally to a circular saw, and more particularly to a clamping device of the circular saw.
As shown in FIG. 1, a prior art circular saw has a work bench 1 on which a cutting device 2 and a clamping member are mounted. The cutting device 2 has a circular blade 2a driven by a motor. The clamping member is formed of a stopping piece 3 and a clamping piece 4. The stopping piece is fastened pivotally with the work bench 1 by a pivot 5. The stopping piece 3 is provided with an arcuate angle scale 3a to facilitate the cutting of a work piece at a predetermined angle. The clamping piece 4 is fastened pivotally with one end of a movable threaded rod 6.
In the process of cutting a work piece A at a desired angle, the stopping piece 3 is tilted, in cooperation with the angle scale 3a. The work piece A is then placed between the stopping piece 3 and the clamping piece 4 before the threaded rod 6 is advanced to drive the clamping piece 4 to press against the work piece A such that the clamping piece 4 swivels so as to urge the work piece A to tilt. The work piece A is then ready to be cut by the circular blade 2a. However, when the stopping piece 3 is swiveled on the pivot 5 for a greater angle, especially at the time when the stopping piece 3 is swiveled in a clockwise direction, one end of the stopping piece 3 is contiguous to the blade 2a and is moved away from the cutting position. As a result, when the clamping piece 4 holds the work piece A the clamping force F1 exerted via the threaded rod 6 is imparted to the work piece A and the stopping piece 3 from the clamping piece 4. In view of the stopping piece 3 having a limited area for resting the work piece A, the clamping force F1 exceeds the outermost side of the stopping piece 3 to form a couple of forces, thereby resulting in the work piece A being held insecurely. As a result, the quality of the work of cutting the work piece A by the blade 2a is seriously compromised.
The primary objective of the present invention is to provide a circular saw with a clamping device capable of holding securely a work piece.
In keeping with the principle of the present invention, the foregoing objective of the present invention is attained by a circular saw comprising a work bench, a cutting device, and a clamping device which is mounted on the work bench and is provided with a stopping member and a clamping member. The stopping member can be adjusted in angle, whereas the clamping member can be adjusted in displacement and rotation. The stopping member is provided in a side wall thereof with a slide member capable of sliding along the side wall in a constant track direction. The slide member has a rest portion which is adjustable in its position such that the rest portion becomes an extension of the side wall of the stopping member thereby resulting in an increase in the surface area of the side wall to enhance the effect of holding securely the work piece.